This invention relates to a reflective optical system that allows a focused beam to scan a surface while respecting simultaneously the f-q and the telecentric conditions. The f-.theta. condition is one in which the scanning angle has a linear relationship with the position of the focused beam on the surface to be scanned. The telecentric optical system is characterized by the fact that the scanning beam has a constant direction and shape. Driven by practical applications, there has been enormous progress in optical scanning over the past several years. However, while much effort has gone to improving the software, relatively little has been done to improve the optical scanning systems themselves. On the other hand, it is possible to simplify considerably the task of the software by designing more sophisticated optical systems which operate at higher speeds and greater accuracy. An f-q telecentric optical system constitutes such a desirable hardware improvement. By introducing the desired amount of distortion in the optical system it is possible to obtain a nearly linear relation between the scanning angle q and the position of a focused beam on the surface to be scanned. If the direction and shape of the beam can also be maintained constant, the systems meets both the f-.theta. and telecentric requirements.